Prometheus: Fuel from the Air
prometheusfuels.com
prometheusfuels.com
But what if the natural gas plants don't have to be a stop gap? Just keep building more and more solar/wind, as much as the land can handle (imagine most of the desert in California converted to solar). Who cares if generation greatly exceeds daily demand. Use all the excess solar/wind to create fuel for the natural gas plants. There's already a vast infrastructure and experienced workforce to do this. Use the fuel during the evening and put any excess fuel into storage, there's so much existing ways to store fuel. Then use that during winter when solar generation decreases.
We need to stop thinking carbon fuel = fossil fuel and so carbon fuel = bad. Carbon fuel is simply a form of energy storage, a kind of "battery".
Not sure how that'd work. To get over 50km range you need a gas engine that provides 100% of the power to the car at highway speeds. A small engine won't pull that off.
There are motorbike engines which produce 30kW (double or triple what a tesla needs to cruise) and can be lifted with one hand. Detune it for longevity, efficiency and noise, add a 10-15kW stator and a 10L tank and you can have a range extender which would take up less than half the boot of a sedan.
If we find our collective sanity and allow travelling long distance at 80km/h that halves.
Hell if we could get our act together and design sane sized vehicles with universal standards you could just stop and swap out a pair of 30kg batteries every hour or two.
>>> If we find our collective sanity and allow travelling long distance at 80km/h that halves.
I'd never want to travel 500km at 80km/h. That is nonsense. Also, having 30kW engine in a car on a highway is a life threatening risk, since you cant easily escape dangerous situations (overtaking other vehicles and acceleration at higher speeds takes way too long) - and we're not even talking about so absolutely hip and unnecessary SUVs or a fully loaded car.
This is solved by having small batteries where fires can be contained and directed out of the vehicle and by using safer chemistries like LiFePo4.
> I'd never want to travel 500km at 80km/h. That is nonsense.
Just because you don't want to shouldn't mean you get to make everyone everywhere carry around 2-4x as much vehicle and battery as they need just to save 20% trip time.
A status quo where a vehicle can travel at a relatively sane, safe (half the collision energy, and braking distance), and efficient speed without fragile ego'd babies going completely postal because they have to wait 30 seconds to overtake is one where people who don't travel often can live with a vehicle that costs a quarter as much, weighs half as much, produces 1/16th the road wear and uses half the energy.
> Also, having 30kW engine in a car on a highway is a life threatening risk, since you cant easily escape dangerous situations (overtaking other vehicles and acceleration at higher speeds takes way too long) - and we're not even talking about so absolutely hip and unnecessary SUVs or a fully loaded car.
You're not burning 200kW for the whole trip. You'd still have your electric motor and batteries, you only need the average power from your range extender. Or if the base range is 50km, your range extender only needs to provide 3/4 of the energy to give you 2-3 hours of time between charge breaks (which will be short)
I would start making a regulation that says all parking-lots MUST have a light-weight roof on top of them on top of which are solar panels.
Imagine all (outside) parking lots having solar-panel covered roofs.
This would be easy to enforce in regulatory terms, which regulating all of deserts is not. You want to have a parking lot? You must have solar panels as well. And it could double as a charging station.
Say goodbye to all rural farmers markets.
Store owner wins because covered parking. Panel owner wins because the increased logistics are offset by free land.
Snow covering the solar panels could be a problem. But perhaps even in winter there is a bit of sunlight which could produce electricity to warm up and melt the snow.
Which sort of begs the question, why isn't this already a thing? Why aren't there companies going to businesses which own parking lots and saying, "Let me lease the air above your parking lot. I'll install and maintain the frames and the solar panels, manage the connection to the grid, the whole lot; I'll pay you $x per meter per month, and your customers have shade."
Yeah it’s a better use of land, it keeps the cars shaded, but no one seems to have figured how to do it economically. Even in Southern California where it’s very sunny, and power is very expensive. I just don’t think it’s anywhere close to being economical. And in other markets the economics are almost certainly worse.
Mass-production is the key to economies of scale. Government policies can play a huge role in steering us towards goals like that.
Why is America so rich? Because of car-industry. And why is car-industry so prominent? Because of the interstate highway system.
Perhaps the Inflation Reduction Act subsidies will, or should, make it a thing.
Government subsidies (incentives) is a good thing if it can save the planet and prevent the devastating floods and forest-fires and drought that is killing us now.
I'd argue that this is likely more challenging than it seems, with city/state/county building codes, plus just building on existing dense spaces, and add to that any grid/utility policies and associated costs to play ball
Meanwhile, the store roof entirely lacks solar.
Nearby Safeway is opposite.
I mean I'd love pricing in the externalities, but then it'd be moot because there'd be a building rather than a parking lot, no walmart, and a train or bicycle rather than a car. There'd also be plenty of roof area for solar panels in any place with a density lower than tokyo metropolis so you wouldn't even need to build supports.
I don't know what the efficiency of the process described in TFA, but from Wikipedia I see that Electricity->Gas->Electricity has an efficiency of 30-40%. There are other alternatives like pumped hydro stations that are way more efficient.
People like to equivocate this with making entire countries uninhabitable or ongoing destruction.
It also requires vast quantities of concrete (and thus has high one time emissions)
We should still avoid it where we can now that we know better.
Hydro power dams use up a watershed, but those are not being built for storage systems. Pumped hydro storage does not consume a watershed or harm wildlife or fisheries. Pumped hydro does not need concrete for construction.
Please do not repeat this falsehood.
- Is at a site of a type that is available with over 100x the capacity of fenging (ie. a hill with a dirt berm would count if there are 4000GWh of hills that could be plausibly used somewhere). If it does this it will help, but is still several orders of magnitude shy of replacing fossil fuels.
- Fulfils your criteria about not destroying an ecosystem.
- Is not built on top of a past project unless there are enough of whatever the past project is to fulfll criterion 1 (ie. a quarry or mine is fine if there are many similar mines or a handful of immense ones) or the cost of repeating the project elsewhere is included.
- Can empty its reserves in 2 months
- Doesn't take up a prohibitive amount of surface area (is at least 20kWh/m^2 or at most 10x the size of a solar array to fill it).
- Has an operating cost under $30/MWh of stored and produced energy
Otherwise pumped hydro does not meaningfully exist as it cannot beat batteries (the thing that is a long way from being good enough to replace fuels) or must destroy a watershed or other ecosystem.
There is no shortage of land to use for elevated reservoirs, and (again) no implied threat to watersheds in building them. There is no need for "at least 20 kWh/m^2". Reservoirs have many uses that all add value. They may store energy and water, provide recreation, habitat, irrigation, and a site for solar, all at once. There is no need for them to store 2 months' power. There is very little economy of scale: a dozen reservoirs are as good as one. Construction cost is not proportional to capacity. At worst, it goes as the square root, to build the perimeter dike.
Extraction rate is a question of how big and how many Pelton wheels attached to generation equipment you care to install.
And, as always, immediate and local cost will dictate choice. There is no need for universal numbers or a single answer for everybody.
Further intntional misrepr#sentation. Batteries solve the short term storage problem (especially sodium ion batteries). You're proposing a much worse solution to the short term storage problem as if it is relevant to the remaining unsolved problem (long term storage). Solving the long term (in space or time) storage problem yields solar supremacy -- conditions in which it becomes untenable to open a new fossil fuel facility or even keep existing ones open in 10 years even with trillions in ongoing subsidies.
> Construction cost is not proportional to capacity. At worst, it goes as the square root, to build the perimeter dike.
You need to make it deeper, or use more land. And when the largest project in the world is at cost parity with batteries in spite of using an existing project and river, that's a damning indictment of anything smaller.
The "largest project in the world" is, by definition, not representative.
There is, because it is the main impedement to the universality of renewable energy.
> The "largest project in the world" is, by definition, not representative.
Yes. Extremely large, recent infrastructure projects by the CCP tend to have vastly lowe stated costs than anything smaller or in another place. If it's unusual\y expensive, show me one which is representitive. Show me a breakdown of a small project (or any project) which uses a typical hill and costs less than projected battery costs at time of completion.
It’s not that great for river fish, either.
But pumped hydro is a completely different proposition.
Meanwhile, each dollar diverted to nukes from building out solar+wind+storage brings climate catastrophe nearer. The immediate cause for catastrophe will be global thermonuclear war triggered by ... more subtle ... effects of the change.
Chemical energy is dense, easy to store, and you need methane for stuff like fertilizer.
Solar energy is basically free ($30/MWh and falling rapidly). The solutions we'lp use are the ones which scale and the ones which are cheapest for storage as it will be much more expensive than the energy.
For storing for a day, that's probably sodium batteries as the cost per MWh through is lowest.
For storing for a year, you want to minimize cost per MWh stored. Right now this looks like methane, maybe hydrogen or for heating, thermochemical batteries.
This is always claimed, and is always false. Please do not repeat falsehoods.
Existing hydro generation needs a watershed. Pumped hydro does not. All it needs is a disused hilltop and earthen dike, and not always the dike.
It doesn't always need the hill: underground cavities work to pump water up out of, and to drain into.
Batteries will always be the most expensive alternative. They will be used in limited amounts, mainly for very short-term (overnight) storage.
Do you have any good numbers on real world projects? I'm very happy to be wrong here, but all the numbers I can find are either lies from nuclear shills or using existing watersheds. Most also only focus on the cost per kW which is higher than batteries and not the relevant metric (as batteries can drain in a few minutes) for season-long storage.
Also a quick back of the envelope seems to suggest emptying and filling lake Baikal could store as much energy as about a billion tonnes of chemical storage. This seems like a reasonable upper bound which would indicate pumped hydro is about an order of magnitude short of solving the problem. Current battery production is nowhere near (total cumulative seems to be about a megatonne chemical equivalent even if it is more than doubling annually it'll take over a decade to catch up), but this is expected because batteries are optimal for short term.
Overall by gut feel it seems a more feasible to make and store ten cubic kilometers of chemical fuel worldwide than move 200,000km^3 of water around.
Dedicated pumped hydro storage is typically quite shallow, with an earthen dike (if needed at all), and the only place with high pressure is at the bottom end of a penstock. It does not need to store years of water; just a day's worth is useful.
To make it impossible to mine more fossil fuels even for a mixture of slave-driving sociopaths unrestrained by law and theocrats actively seeking apocalypse we need to be able to use a MWh at night in mid winter that was produced at 2pm in summer for less than around $40 and then do it another billion times without hitting some resource limit. Hydrogen with storage is shockingly close, and if synthetic ammonia/methane or metal hydride get over the line, noone will look at fossil fuels again.
You seem to be telling me that pumped hydro is already there, but I can't find a decent source agreeing with you (or any numbers dealing with this use case for that matter).
There are actually dozens of shallow reservoirs behind earthen dams way high up in California's Sierra Nevada mountain range, many almost a century old, constructed with bulldozers that used pulleys instead of hydraulics, hauled up there on fantastically bad cart-track roads. The reservoirs feed penstocks down to Pelton wheels thousands of feet below. For storage, they just attached pumps to the penstocks to push water back up.
And I can attach a washing machine motor to my water tank. If it produces basically nothing and costs double the alternative, it's not relevant to the discussion.
> There are actually dozens of shallow reservoirs behind earthen dams way high up in California's Sierra Nevada mountain range, many almost a century old, constructed with bulldozers that used pulleys instead of hydraulics, hauled up there on fantastically bad cart-track roads. The reservoirs feed penstocks down to Pelton wheels thousands of feet below. For storage, they just attached pumps to the penstocks to push water back up.
So there are no new projects which not destroying an ecosystem that are on cost parity with batteries then?
Also as an aside, how pathetic is capitalism as an organizational system that we can't achieve the types of things that were done with horses and carts and pulley bulldozers in the past?
This makes it better than existing batteries for ~1 day time scales and roughly on par with the upcoming generation of things like sodium batteries.
It's not a clear indicator as it's obviously optimized for power, but these all seem to be big advantages specific to the site which would indicate that an artificial reservoir would have trouble competing even against batteries.
Different sources have figures that differ by a bit (presumably projections vs actual) and most seem to have some mistakes. Here's one. https://www.nsenergybusiness.com/projects/fengning-pumped-st...
I could believe that you might improve storage/cost by a factor of 10 if you found a suitable reservoir by reducing power, but that seems to back up my initial assertion that you need specific geography and to significantly change the ecosystem fairly well.
As such it seems like it is not much better than a battery for displacing fracked methane, oil, or nuclear for mediating seasonal variability (which is what synthetic denser-than-hydrogen fuel is for as it is optimized for approximately zero cost per capacity at the expense of the highest cost per joule with competitive cost per watt).
Plus batteries still have a 10-20% efficiency benefit.
We also have underground compressed air using existing deep cavities, and undersea compressed air. And underwater buoyancy, drawing floats down toward seafloor-mounted pulleys, using a winch and motor-generator on shore. Demand will not exceed our capacity to make cables and floats.
But the real answer is that there is nowhere even close to as great a need for long-term storage as you imagine, just as there is not much petroleum stored today. Petroleum is extracted and delivered continuously and reliably. Myriad tropical solar farms will synthesize ammonia year-round, shipping anywhere needed on demand, so storage is needed only until the next shipment arrives.
And HVDC transmission lines will move power from where it is being produced to where it is not, over 1000s of km, at a wholly tolerable loss rate. Much of this will move power eastward from afternoon production and westward from morning production, but also generally fill in for local production and storage shortfalls everywhere.
So Finland can have ammonia shipped in continuously all winter long, just as they ship in petroleum and NG today. Transmission lines will compete for that business.
These are more technologies that compete with batteries, not fuels. And poorly at that. CAES in ideal sites might compete with batteries for a while yet, but the others do not. Even a single truck full of ammmonia can store the equivalent to tens of thousands of cubic metres worth of displacement storage. A cubic metre float in a 500m deep body of water can store 5MJ, or about the same as a battery you can lift with one hand and buy for a few hundred dollars.
> But the real answer is that there is nowhere even close to as great a need for long-term storage as you imagine, just as there is not much petroleum stored today. Petroleum is extracted and delivered continuously and reliably. Myriad tropical solar farms will synthesize ammonia year-round, shipping anywhere needed on demand, so storage is needed only until the next shipment arrives.
Moving energy 2000-4000km as not-electricity is strictly a harder problem than storing it for 6 months and is solved with a subset of the same solutions. The main upside is energy input is cheaper and there is less idle time. This is definitely part of the solution but comes under the same heading.
HVDC systems are a solution for most of the issues, but distant solar isn't completely uncorrelated. Also no country is going to stake their survival on a system with cascading failure modes that can be triggered by anything from war, to a heat wave, to a blizzard, to a cyclone, to a forest fire, to political games. Thus capacity for months of backup is still required.
All of this is moot anyway because your other comment led me to find sources stating green ammonia is already within 50% of cost parity with fossil fuels for the cheapest solar energy sources and ammonia fuel cells are now viable as well with the same technology. Between that and thermochemical storage, fission is obsolete immediately and fossil fuels only need one more price shock for the transition to start.
Also none of this supports your original assertion that pumped hydro meaningfully exists in a non-ecosystem-altering way.
You are always free to invent falsehoods about pumped hydro, as about anything else.
PVs solve net energy needs. Perovskites might even make them do so without needing strategic mineral reserves. But they don't really provide energy security, and keeping fossil fuel infrastructure working for 1 month in 30 is extremely costly.
> You are always free to invent falsehoods about pumped hydro, as about anything else.
Then show the real numbers. I did. Demonstrate it being viable as a significant portion of primary energy in a typical country as a new project.
Better than fuels at present, but inherently fragile so not a complete solution. Also those are just claimed building costs not including operation (and assuming it lasts about as long as the pv), and the natural monopoly spawned always winds up being a massive tax money sink, so it's not clear that building thousands of hvdc lines is going to work out.
AFAIU it is even less fragile because it's usually 'point-to-point', which means to integrate it into the grid you need very modern substations with the ability to 'transform' the DC into the AC of whichever pre-existing grid by means of mass cascaded https://en.wikipedia.org/wiki/Insulated-gate_bipolar_transis...
Which in turn makes the grid around these substations smart, the more, the smarter. Because you have much better ability to switch and regulate(diversion from same frequency in AC-grid due to dynamic load or failure) much faster.
Think of the difference between the large external 'power-brick' for older laptops vs. the small switching power-supplies for contemporary notebooks. Just in reverse.
Nothing? The point is transmission is extremely fragile. To physical conditions (weather, accidents, faults). To market effects (massive price gouging during those failures due to lack of buffer). And to market failures (harmful monopolies always form around private utilities and neoliberals always privatize utilities).
Then if the oceans are involved, cost becomes a non-starter.
That remains to be seen. Some people seem to think different.
https://electrek.co/2022/04/21/the-worlds-longest-subsea-cab...
&
https://xlinks.co/morocco-uk-power-project/ is just the latest of those ideas/projects. I think it was on HN too.
This is called a dystopia.
Is a desert covered in solar more or less a dystopia than the smog clouds that currently engulf LA?
Same as Green Hydrogen, you'd only burn these if you couldn't directly electrify or battery power it.
Otherwise you're using electricity you could have used directly, to make the fuel at a big loss of efficiency.
A very bad one at converting from/to electricity. Obviously, if you start from something else, e.g. dinosaur, then it's great.
But if you want to use it to store electricity, it's extremely poor due to the conversion involved, any kind of battery (and iron battery is a promising one!) is much better.
Good luck trying to break even with as many batteries as would be needed for weeks or months worth of energy/electricity.
If local storage looks likely to be used up, and you can't schedule power from a transmission line, you order a shipment of ammonia from any of many tropical solar farms.
Let's say renewable electricity generation capacity increases significantly (which needs to happen as we all know), then due to fluctuations around the year of solar irradiation alone there need to be weeks if not months worth of electricity storage (in whatever form).
Ammonia is exactly that, storage of energy that gets converted to electricity, to keep up with grid demand. Ammonia then _is_ your weeks/months worth of storage.
Do you think utilities store months of fuel, nowadays? Or do they rely on regular deliveries? Do you think relying on regular deliveries of ammonia, in winter, would be much different from relying on deliveries of NG year-round, as today?
Yet I'd assume _most_ places in the global west still have fluctuating irradiation and wind to a degree that makes weeks worth of storage necessary.
> Do you think utilities store months of fuel, nowadays?
The utilities probably only to a certain degree. But it doesn't really matter who stores the fuel, right?
> The United States has the world's largest reported strategic petroleum reserve, with a total capacity of 727 million barrels. If completely filled, the U.S. SPR could theoretically replace about 60 days of oil imports. [1]
These reserves are of course not used to supply power plants.
But I'd bet as soon as the renewable slice of electricity generation exceeds some 50-60 % of total supply, the authorities will not have days but weeks or maybe months worth of natural gas or hydrogen or ammonia stored to supply the grid (with according power plants) over extended periods of low renewable generation.
Just thinking about how essential the electric grid is for society to work, convinces me that it won't be days worth but significantly more.
[1] https://en.m.wikipedia.org/wiki/Global_strategic_petroleum_r...
As to deliveries from around the world. Any country will of course make a trade off between the political goal of independence or self sufficiency and economic considerations. Countries that have sufficient renewable electricity generation potential to be independent from external supplies will rather try to avoid external dependency, don't you think?
Which would require storage.
Also, imagine what happens as combustion engine cars get replaced more and more by EVs. The strategic petroleum reserves probably become less important and grid stability becomes more important. And I don't think the EV batteries are going to provide enough buffer to enable a stable grid all year round.
You miss the point about the tropics, again. Places with reliable insolation will be exporters of synthetic fuel. None will have monopoly power, because the sun shines on them all equally. Northern countries may buy as much as they can use from them, so will not need more storage than for the time until the next shipment.
The US keeps a "strategic petroleum reserve" specifically because it has been subject to embargo by a limited group of producers. There can be no such embargo of synthetics from renewables, so no value in any such "strategic reserve".
Imagine some non tropic country were to gradually increase its renewable electricity generation capacity. Solar on more and more roofs. The country now reaches a capacity that matches its peak electrical power consumption when the sun shines at noon and the wind blows everywhere.
Now there are two possibilities.
A. They stop increasing generation capacity. When generation is _below_ peak (because evening and no wind) this country has to rely on storage or imports.
B. The country continues increasing renewable generation capacity, so when the sun shines and the wind blows, they have excess electricity. Which they can store in batteries or as hydrogen or derivatives.
Why should any country choose A over B?
And why should they not continue to increase capacity (until all reasonable surfaces are covered) in scenario B until they maybe even are independent?
I'd say the only reason not to do that would be if imported energy were cheaper.
Clearly B is better, but they get to A on the way there. On the way to B, they may find they import power infrequently enough that they prefer to stop building out. That is a legitimate choice for most.
Cost is all-important, in energy policy.
Although the carbon emissions would be net neutral, Such a system would not be greenhouse gas neutral. Some methane from the natural gas plants will leak out. This is a gas that is 25 times more potent than CO2 over a 100 year timeframe [1].
Nitrous oxide, which is a byproduct of the combustion process, will be emitted and this gas is 298 times as potent as CO2 over a 100 year timeframe.
[1] https://www.epa.gov/ghgemissions/overview-greenhouse-gases
This is a solved problem. Please do not engage in idle, misinformed concern-trolling.
Point here being that you could avoid this whole class of problem with energy storage technology. Although Lithium Ion batteries present their own technical issues to solve, there are other energy storage technologies that show promise [1].
Regarding your comment, you took a leap in assuming this was assuming it was idle, misinformed concern-trolling. It could be that I am ignorant of the NOx scavenging, it could be that I am aware of it and take issue with it. Both possibilities you ignored.
Please review the HN guidelines, you may find this passage relevant,
Please respond to the strongest plausible interpretation of what someone says, not a weaker one that's easier to criticize. Assume good faith.
Power-to-gas has been the proposed solution for seasonal storage for a long time now. Few people who are interested in the topic believe that current battery technology can scale to store a couple of weeks worth of power. Maybe something like iron-air batteries, but the proven technology is elecrolysis optionally followed by upgrading the hydrogen to methane or ammonia.
But I wouldn't worry about putting them in a landfill either. They're not particularly dangerous.
Voicing worries about used up solar panels is cheap concern trolling.
Deserts are a dumb place for panels because the panels get hot and dusty. Heat cuts both conversion efficiency and panel lifetime. Accumulating dust can block as much as 80% of light.
The best place to site panels is floating on reservoirs and canals, where temperature is kept in check. Nobody knows how long floating panels could last. At the same time, they cut evaporative loss and biofouling, and provide complex habitat under for water creatures.
Next best is in farm fields, in rows with room for a tractor and equipment between. There, they cut heat stress and water loss, and run cooler than in desert or on rooftops. Most plants can use only a very limited amount of full sun in a day, and just endure more, welcoming shade. The panels produce year-round, complementing seasonal farm revenue.
A good way to deploy in fields is bifacial panels in vertical fence-rows running north-south to pick up morning and afternoon sun, during peak demand. Panels stay cooler, don't gather dust, and are out of the way of farm equipment; and fence mounts cost less than others. This works well in pasture, too, where livestock keep down weeds and benefit from shelter. (E.g., sheep produce better wool.)
For some crops, growing directly under (near-) horizontal panels protects them from harsh weather, often multiplying yield. A T-shaped mounting is practical here, with room under, and a gap between, for farm equipment.
Since the land is doing something else of value, there is no need to pack panels as tightly as they will go. There is way, way more viable dual-use farmland than could ever be needed for energy, so only the best places for it need be used.
Hydrocarbons are a poor choice of storage medium, because you need a source of carbon to make them, which is then released into the atmosphere when you burn it.
Hydrogen just needs water for feedstock. It is easily stored underground, including in used up fracking fields. It may be transported in liquified form, similar to LNG.
Ammonia needs just water and air as feedstock. It stores in liquid form under light pressure at room temperature, and transports well.
Hydrogen and ammonia are both massively valuable as feedstock for myriad industrial, transport, and agricultural processes, so when your tankage is full, all your excess production may be sold for ready cash.
What's the magical material in the Faraday reactor that can somehow combine CO2 + water to form hexanol? I've never heard of such a process occurring (again, probably my ignorance). And then similar question for the separation filter?
If I had to guess an analogy, it strikes me as similar to mining and then recovering + refining miniscule fractions of uranium isotopes at a similar energy cost. And when you require that much energy/cost to get some small amount of material, it had better be very valuable, and not something you just burn at $3/gallon.
But I am glad to be educated on how this is breaking that analogy.
Dude, where's my fuel? - https://news.ycombinator.com/item?id=31264388 - May 2022 (183 comments)
Prometheus Fuels (YC W19) Closes Series B with $1.5B Valuation - https://news.ycombinator.com/item?id=28631067 - Sept 2021 (121 comments)
Launch HN: Prometheus (YC W19) – Remove CO2 from Air and Turn It into Gasoline - https://news.ycombinator.com/item?id=19842240 - May 2019 (565 comments)
A Quest to Make Gasoline Out of Thin Air: Prometheus (YC W19) - https://news.ycombinator.com/item?id=19792412 - April 2019 (279 comments)
How about just some static text explaining what they're doing? I don't need a web site with overcomplex crap that doesn't work.
The most important cost after electricity is equipment cost,
typically called capital cost. Adding up the electricity and
CO2 costs, we get $1.86/gallon. If we want to stay below $3.00/gallon
(for example), then we need to keep the capital and maintenance costs
less than $1.14/gallon. Our cost models tell us that we can have
capital and maintenance costs that are significantly lower than that
For reference, Prometheus costs $1.86/gal to operate and they are aiming to reduce the cost of the machine so it can be produced including capex at $3.00/gal.
[0]: https://www.energy.ca.gov/data-reports/energy-almanac/transp...
($3/gallon) / (8.9 Kg/gallon) * (907 Kg/ton) = $306/ton
That's the only thing they market it as
1) Capturing CO2 from the air and making fuel from it, or
2) Capturing CO2 from the air, sequestering it, and using it to offset the CO2 produced by using fuels derived from petroleum.
If 2 is cheaper than 1 then this process is useless anytime soon.
It is inherently cheaper to make a low energy, high carbon, biofuel than it is to make a high energy fuel that can actually be used. And it is cheaper exactly by the energy you don't have to leave in the fuel. Furthermore for many applications, electrical+batteries is more efficient than fossil fuels. So with projected near-term technologies, it makes no sense to make a round trip through fossil fuels.
Take a state of the art green hydrogen system at about $4/kg (and falling rapidly with projections as low a $1 in a decade)
Let's assume we have a machine that can sequester 80mJ worth of CO2 from fossil fuels or about 0.75kg of carbon or 200g of CO2 from the air for $1
If the cost of extracting, refining, storing, transporting and dispensing 80mJ of fossil fuels ever exceeds $3 (or the cost of the green hydrogen goes down equivalently) you've lost instantly.
But it's much worse than that, because that 80mJ of fossil fuel required about 160mJ of fossil fuel to be burnt durng extracting, refining, storing, transporting and dispensing, so now you have to get it for $1 (less than the current market price of methane).
You could argue that you can use green energy for all of the steps to get the fossil fuel, but that's just an incredibly stupid, expensive, polluting and roundabout way of makng a water electrolyzer.
Locally made Hydrogen becoming a more economical fuel than fossil fuels by 2035 is an inevitability. The only relevant question is whether we can find a cheap and efficient way of storing it or turning it into something at least as heavy as methane or ammonia.
Batteries will always be better per joule dispensed and thus for daily or even weekly fluctuations, but a year of capacity is unsolved and chemical storage has some pretty big upsides.
Not that anybody needs that, because tanks of ammonia are transportable from places that produce reliably.
More seriously countries in high latitudes need a winter's worth as a strategic reserve to avoid being left in the situation much of europe is in now.
Ammonia is unfortunately not yet provably viable on a cost basis, but it's probably the most likely of the top three contenders; the others being, methane, and metal hydride.
Methane is much safer, has existing infrastructure and appliances, works in petrol cars with minor change, and seems to require less extreme conditions and complex plant so may be a viable way to take advantage of carbon sources at smaller scales.
Metal hydride seems like the only potential household scale electricity->fuel->electricity option (not that that's a necessity or even overly efficient, but an affordable complete standalone system would close the book on fossil fuels and finally end the nuclear shilling) as fuel cells, solar power, and electrolyzers can already be had for a combined price of well under electricity retail. It is also safer than ammonia (at least the heavily endothermic versions are). What makes you dismiss it entirely as a research avenue (other than being far too expensive at present)?
Metal hydrides can store as much hydrogen as you have bought pricy porous metal. In that way it is much like a battery, with the added complication of the fuel cell and electrolyser limiting discharge and charge rate. I.e., want more watts in, buy more electrolyser, more out buy more fuel cell, more storage more pricy metal.
The appeal of liquid fuels of various sorts is that tankage is cheap. Want more storage, buy more tank. Tank empty, call for a truck to fill it. When your tankage is full, you can fill somebody else's, and call them up to haul away when full, and pay you. They won't want to leave expensive metal or batteries with you to be charged up when you feel like it. But leaving empty tanks around is an easy choice.
Ammonia is a slam dunk for utility scale if it ever hits $30/MWh, but I don't think it's so clear cut otherwise (methane may even beat it as it's not clear to me the cost of harvesting CO2 is strictly more than the cost of running at the higher tempsand pressures for ammonia). When utilities are charging some 40c/kWh and over $1/day connection fee and feed in is 5c it's almost always the correct choice to max out the panels. There are a lot of people with energy available during summer that have 30c/kWh + $400/yr + a couple hundred of fuck you money they'd be happy to spend to move it to winter and not continue feeding the ghouls who have been bilking them as well as not having their inverter turned off when there's a brownout due to mismanagement. That becomes about $300/MWh or more than an order of magnitude over what the wholesale costs are.
Any option that is safe enough not to have an excuse for the utility lobby to ban it and under 5x the current cost of methane is going to have a lot of people interested.
Ammonia can be synthesized electrically from water and air by a cheaper and lower-volume process than is used today to make it from air and NG.
Methane has the unfortunate quality that, for practical transport in liquid form, it needs to be at cryogenic temperature. Ammonia stores and transports in liquid form at room temperature and not too high pressure.
But ammonia is not suitable for home use because of its toxicity. Methane is not, either, because it needs reliable cryogenic refrigeration, or extreme pressure. Likewise, probably, hydrogen.
You probably need synthetic propane for domestic storage, a more expensive proposition than others.
This is news to me. Can it be done with a catalyst as abundant as nickel, or is it only platinum group or similar? Does it happen in conditions as easy to make as a sabatier reactor (or even better, one of the nickel catalysed methane reactions)?
Edit: Just found the magic words Barium Zirconate proton conductor. I think it works out to $130/MWh (including hydrogen?) https://www.energy.gov/sites/default/files/2021-08/12-proton... and seems to apply to fuel cells as well. This basically obviates nuclear, and is only a factor of four (three with unwanted solar power?) off of replacing many fossil fuels if true. Why isn't it getting more attention? This is far more important than fusion.
> But ammonia is not suitable for home use because of its toxicity. Methane is not, either, because it needs reliable cryogenic refrigeration, or extreme pressure. Likewise, probably, hydrogen.
Methane stores okay in stationary pressurized metal vessels at densities on the order of 1MWh/m^3 or about 5x as much as lpg albeit with a more expensive high pressure tank. This is bulky, but viable to store behind the garage or underground or similar. It's harder to make into electricity though without 70% losses. Hydrogen doesn't really pass this test as it's about 5x again (there's probably enough room for many uses even if people need 50m^3, but a 300bar tank that won't embrittle is far too expensive).
Small (<1kg) retail metal hydride containers are currently about the price of retail batteries by the one shop I found ($8-9k for 3000L). Given it's an extremely niche industry without the benefits of mass production, I see this as very weak evidence for rather than against the hypothesis that a 20 price reduction in 10 years if you want 20x the storage is as plausible as the other things we're talking about.
Not sure which percentage of the cost of the whole system comes from the hydrogen storage in these standardized steel containers.
To me it looks like the bigger issue for most property owners would be finding the space for putting enough of these containers (guess they need to be kept outdoors for security reasons) rather than the cost of the containers themselves.
Ammonia (as the other commenter mentioned) is a major contender, but I expect it will be blocked soon for small scale by the methane lobby with the rationalization of "der terrerrists haev nitrogen'. Synthetic methane is the other major contender.
The linked company appears to be able to handle this. Although there aren't that many installations of their system. (Which is probably due to the system not yet reaching break even soon if at all, because energy is still quite cheap.)
As soon as an ammonia fuel cell is available as mature tech, ammonia will probably be the storage of choice for large scale systems.
But for residential storage hydrogen has the advantage that an electrolyser is comparatively simple mature tech, while ammonia synthesis probably won't be soon if ever.
I did find some alibaba listings for pressure tanks. The cheapest believable ones were about $100 for a 50L 300bar tank. This works out to about $3k for a MWh of storage. You'd have to fill and empty it a couple of times a year for 20 years to break even vs nuclear just on the storage cost.
It might beat retail in some areas though, and you'd need 50 or so of them to over winter in cold areas.
Sounds like medium term storage (weeks) is solved if $100/tank (or even $1000/tank) is doable though.
If the goal is to remove fossil CO2 that is already in the air, then this process is doing more than it needs to and so won't compete with just running their system and using the output from the first step as a chemical feedstock instead of using extra energy to turn it into a classic fuel.
But, the key missing option is 3) use the electricity you were going to use to make the fuel to do the end task directly and much more efficiently, and without fossil or recycled carbon being involved.
Their pitch is a bit like: “Someone else has invented the replicator machine that makes any food you want in Star Trek and our business will use that basically free, essentially limitless food as an input to our bioreactors to make Quorn meat substitutes."
Quorn is a good thing now, when meat involves expensive, cruelty, waste, carbon and disease. Once you have near limitless food on tap though, it becomes a very niche product.
Fortunately there are now better alternatives, and Quorn can go quietly out of business.
Batteries solve this somewhat, but are big, heavy, and expensive.
Fuels are small, light, cheap to store, and inefficient.
You're not going to want to store energy for 6 months with batteries even if they hit the $30-60/kWh range.
You're not going to want to store energy as fuel for a few days unless you really need to pick it up and move it.
Solar derived fuels are nearly competitive with nuclear ($130/MWh with maybe $10-20/MWh to burn it according to this claim https://www.energy.gov/sites/default/files/2021-08/12-proton... vs $100 for nuclear).
Other safer fuels are not far behind for applications closer to people.
The energy component of that cost is going to halve or better on a fairly predictable schedule around 2035, so if the cost of the manufacture can be brought down to half or better there's not really any reason to continue with fossil fuels.
So the correct metaphor is a replicator that only makes perishable non refrigeratable foods on public holidays. To be able to eat the rest of the time you'll need to make a lot of soup even though you don't really like soup.
Also worth noting is this particular project is just buzzword soup that absolutely reeks of a pump and dump scam, and is closely tied to y combinator. Please don't dismiss real e fuel projects when they run off with a few billion dollars of investor money in two years. Edit: found their news article where they break down costs a bit, might not he a scam -- the slicm marketing still reeks of solar roadways though.
This is a classic HN response, talking about how an artistic website should ideally be reduced to some characters on a screen. But I am curious, what browsers did you use?
Edit: I see other people complaining that it doesn't load for them. So maybe not so slick after all!
TypeError: Cannot read properties of undefined (reading 'baseCamera')
Heavy investment in nuclear could create a grid with such cheap energy we can use all the excess capacity for fuel synthesis along with renewables.
Hydro generation sites are used up. We are demolishing dams, nowadays, because the fisheries they displace are way more valuable. (This does not make pumped hydro a bad idea: pumped hydro does not destroy fisheries.)
A calculation by Jean Marc Jancovici showed that for a small airport (GVA in this case) you'd need half a dozen nuclear reactors just to produce the fuel for departing flights. That's obviously assuming this kind of technology is functioning and has 100% yield.
I'm not saying that these technologies are not to be pursued, but thinking that we (the rich) can keep flying as much as now due to a miracle technology is unsupported by Science, to say the least.
ps: i did 2 postdocs in material science trying to improve various industrial/energy technologies. there's no miracle.
Last time I checked, land wasn't cheap and they weren't making any more of it.
Maize and wheat yield is reduced a bit, without, but the year-round revenue from solar panels easily exceeds the difference.
I'd call that an argument from laziness.
> Last time I checked, land wasn't cheap and they weren't making any more of it.
Land that is remote, not fertile and that doesn't harbor any natural resources is actually rather cheap. Moreover, "they" are making more land in certain coastal areas where land is expensive.
Then it occurred to me that even nature hasn't really solved ocean surface plants, what could be a more clear indicator that it's a really hard problem...
The limit is our ability to scale algee, but the lab results also show that the numbers are right.
[1] https://www.wolframalpha.com/input?i=%286GW%2F%2820W+per+squ...
In clear weather, a surface perpendicular to the sunlight gets about 1 kW / m². So 1 GW would take a square kilometer. If our solar cells are top-notch 25% efficient cells, 1 GW will take 4 km² at best weather. And we need many multiples of that.
Verily, Sahara must be the best place for such an oil factory. Maybe some of the US Midwest and West, with many sunny days. And, unlike the cute pictures on the side, they will need to be massive, all the way to the horizon.
Maybe with a few nuclear plants thrown in if we learn to build them efficiently again.
Out of curiosity, I tried some napkin math on this. If Nevada went whole hog, used say, 1% of their total land for solar, they could produce almost half the electrical needs of the US, if I haven't mucked up the math too much.
Sounds plausible, but 1% of Nevada's land for solar would indeed be 'all the way to the horizon' in many places.
let's also assume we stabilised biodiversity and avoided a mass extinction.
should we continue to produce massive amounts of energy so that some can commute by plane daily and others can stream cute kitten video in 8k?
If the only way to keep that up is burning oil, then no.
Please also note that some of the most intense producers of CO2 are poor(er) countries which burn coal because it's cheap. Even natural gas can be too expensive for them, let alone solar or wind installations.
I wonder when the West would consider buying and converting such plants. It's likely feasible in Africa, hardly so in China.
It's also on the coast for access to coolant water.
It seems very difficult to place huge facilities like this with all the staff and security requirements on waterfront property when you can stick a solar panel on or next to just about anything.
Also electrifying entire trucking and car fleets will take decades.
This provides a means of producing an incredibly densely stored source of energy from abundant inputs, that is the same price as oil.
It can solve for the problem of net zero production and transportation of equipment used in renewable energy production, for example, using present day transportation technology.
There are no silver bullets, but all of these innovations add together in order to create a combined solution to the worlds energy problems.
i worked all my professional carrer in science and innovation, if you have a reference for that statement i'd be glad you share it. maybe i missed something.
If we had some ham, we could make ham and eggs, if we had some eggs.
"Highly economical fusion" is probably an oxymoron.
As we reign in the gratuitous subsidies to the fossil fuel sector, the question then becomes can we provide the plant and operational costs to store electricity chemically for $30/MWh (or as fossil fuels get more difficult to extract, $60 or $100).
Given that it's a brand new industry and you can do it right now with hydrogen for $200, energy included, then we only need to price in a fraction of the externalities right now and airline operators are going to be looking pretty hard at various green fuel options.
the problem is that rail is "boring" and rarely get sufficient funding.
It's wired vs wireless ethernet. Which do you have in your home?
Then other things become more important, and drive choices.
I agree we should do more trains, but they are limited to around 1500km per trip before flying is enough better that you look like a fool for suggesting it.
I'm not convinced trains are more efficient than planes at that distance either - I don't' know how to analyses it, but planes see much less wind resistance because of altitude.
https://terraformindustries.wordpress.com/2022/07/24/were-go...
On the land-use of the solar panels themselves, I wonder if at some point in the future it might be possible to beam a directed laser to earth from space-based solar arrays, so the earth-based footprint is reduced.
Google tells me [0] that total fuel consumption by commercial airlines in 2019 was 95 billion gallons. One gallon of fuel has around 33 kWh of energy.
Power capacity needed to produce that amount of energy in a year is around 358 GW.
Total world electricity production in 2020 was around 3000 GW-year [1].
[0] https://www.google.com/search?q=total+yearly+aircraft+fuel+u...
[1] https://www.google.com/search?q=total+world+electricity+prod...
1) number of barrels of jet fuel per day in switzerland:
34000 barrel / day = 0.39 barrel / s
https://www.indexmundi.com/energy/?product=jet-fuel&graph=co...
2) energy in a barrel of jet fuel:
1700 kWh / barrel = 6120000000 J / barrel
3) total power for switzerland:
2.4 GW
so more like 2-4 reactors for all switzerland.
Prometheus can turn 77kwh of electrcity into 1 gallon of fuel.
Jet plane with range of about 7000km has 52000 gallons so roughly
4GWh of electrical energy in to make the fuel, about half of which is lost as heat and the other half moves the plane.
So the real question is, do you have a better use for that 4GWh of electrical energy? (Or more generally, and back to car size would you prefer 77Kwh of electricity or a gallon of fuel?)
Carbon free electricity so cheap that you can make carbon containing fuels for less than fossil fuels is like a very heavy carbon tax in impact. Yes you can do whatever you like with the fuels, but since you pay directly for it, the market will respond by finding cheaper and more efficient ways to do the same thing, using the electricity directly or as a cheaper to convert fuel.
Their pitch kind of makes sense for long distance flight, but unless it's a classic car that you only drive once a year, this fuel will have the exact same impact as a heavy carbon tax on the market for motor vehicles i.e. they'll be scrapped and replaced with EVs that are cheaper and cleaner to run.
Or is the fact of using renewables to power going to hopefully net positive over a long enough time scale?
Governments could also pay to have carbon pumped out of the air and buried back into the ground as reconstituted liquid fuel.
Plus, having much better carbon capture tech means just simply removing CO2 for some sort of inert long term storage is cheaper.
They could even run it when electrical demand is low (sucking up extra watts and essentially subsidizing renewable over-building) and then maybe even use their output to fuel a power station, to help shave demand peaks. So, acting like an energy storage device. Of course there are plenty of other ideas in the energy storage device space, and probably most of them are more efficient, but they don't produce legacy car fuel.
Anyone with a couple billion dollars laying around ?
If they just implemented their technology as designed, they would be carbon-negative. So they have to cause more carbon to be released, in order to get to break-even.
They are crowd-sourcing increasing their carbon footprint via the power requirements to load their website.